STM32F407独立看门狗

1万 · 2021-9-6 15:44

iwdg.c

#include "iwdg.h"

//初始化独立看门狗
//prer:分频数:0~7(只有低3位有效!)
//分频因子=4*2^prer.但最大值只能是256!
//rlr:自动重装载值,0~0XFFF. (4095)
//rlr:重装载寄存器值:低11位有效.
//RCC=32Khz
//时间计算(大概):Tout=((4*2^prer)*rlr)/32 (ms).
void IWDG_Init(u8 prer,u16 rlr)
{
IWDG_WriteAccessCmd(IWDG_WriteAccess_Enable); //使能对IWDG->PR IWDG->RLR的写

IWDG_SetPrescaler(prer); //设置IWDG分频系数

IWDG_SetReload(rlr); //设置IWDG装载值

IWDG_ReloadCounter(); //reload

IWDG_Enable(); //使能看门狗
}

//喂独立看门狗
void IWDG_Feed(void)
{
IWDG_ReloadCounter();//reload
}

iwdg.h

#ifndef _IWDG_H
#define _IWDG_H
#include "sys.h"

void IWDG_Init(u8 prer,u16 rlr);//IWDG初始化
void IWDG_Feed(void); //喂狗函数
#endif

1万 · 2021-9-6 15:46

main.c 使用基本定时器6喂狗

int main(void)
{
/*看门狗*/
IWDG_Init(3,5000);//看门狗 5S    实际1S
/*84M/8400=10k=0.1ms  10*0.1ms=1ms */
TIM6_Config(10-1,8400-1);  //TIM6 定时喂狗中断优先级主0子0

while(1)
{}
}

timer.c

//TIM6  喂狗
//基本定时器6中断初始化
//这里时钟选择为APB1的2倍，而APB1为42M，即TIM6时钟为84M
//arr：自动重装值。例1000-1，计数器从0数到1000，即T=1000*1us=1ms
//psc：时钟预分频数。例84-1，若时钟为84M,则分频后为84M/84=1MHz 即1us
//定时器溢出时间计算方法:Tout=((arr+1)*(psc+1))/Ft us.
void TIM6_Config(u16 arr,u16 psc) //1ms
{
TIM_TimeBaseInitTypeDef TIM_TimeBaseInitStructure;
NVIC_InitTypeDef NVIC_InitStructure;

RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM6,ENABLE);  ///使能TIM6时钟

TIM_TimeBaseInitStructure.TIM_Period = arr; //自动重装载值
TIM_TimeBaseInitStructure.TIM_Prescaler=psc;  //定时器分频
TIM_TimeBaseInitStructure.TIM_CounterMode=TIM_CounterMode_Up; //向上计数模式
TIM_TimeBaseInitStructure.TIM_ClockDivision=TIM_CKD_DIV1;
TIM_TimeBaseInit(TIM6,&TIM_TimeBaseInitStructure);

TIM_ITConfig(TIM6,TIM_IT_Update,ENABLE); //允许定时器6更新中断
TIM_Cmd(TIM6,ENABLE); //使能定时器6

NVIC_InitStructure.NVIC_IRQChannel=TIM6_DAC_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority=0x00; //抢占优先级0
NVIC_InitStructure.NVIC_IRQChannelSubPriority=0x00; //子优先级0
NVIC_InitStructure.NVIC_IRQChannelCmd=ENABLE;
NVIC_Init(&NVIC_InitStructure);
}
//喂狗 1ms
void TIM6_DAC_IRQHandler(void)  //中断
{
if(TIM_GetITStatus(TIM6,TIM_IT_Update)==SET)
{
IWDG_Feed(); //喂狗
}
TIM_ClearITPendingBit(TIM6,TIM_IT_Update);
}